Micro-abrasion of flint artefacts by mobile sediments: a taphonomic approach

Fluvial redeposition of stone artifacts is a major complicating factor in the interpretation of Lower Palaeolithic open-air archaeological sites. However, the microscopic examination of lithic surfaces may provide valuable background information on the transport history of artifacts, particularly in low energy settings. Replica flint artifacts were therefore abraded in an annular flume and examined with a scanning electron microscope. Results showed that abrasion time, sediment size, and artifact transport mode were very sensitive predictors of microscopic surface abrasion, ridge width, and edge damage (p < 0.000). These results suggest that patterns of micro-abrasion of stone artifacts may enhance understanding of archaeological assemblage formation in fluvial contexts

Resolving the unresolved tribe: a molecular phylogenetic framework for the Merremieae (Convolvulaceae)

Tribe Merremieae, as currently circumscribed, comprise c. 120 species classified in seven genera, the largest of which (Merremia) is morphologically heterogeneous. Previous studies, with limited sampling, have suggested that neither Merremieae nor Merremia are monophyletic. In the present study, the monophyly of Merremia and its allied genera was re-assessed, sampling 57 species of Merremieae for the plastid matK, trnL–trnF and rps16 regions and the nuclear internal transcribed spacer (ITS) region. All genera of Merremieae and all major morphotypes in Merremia were represented. Phylogenetic analyses resolve Merremieae in a clade with Ipomoeae, Convolvuleae and Daustinia montana. Merremia is confirmed as polyphyletic and a number of well-supported and morphologically distinct clades in Merremieae are recognized which accommodate most of the species in the tribe. These provide a framework for a generic revision of the assemblage.

Characterization of para-Nitrophenol-degrading bacterial communities in river water by using functional markers and stable isotope probing

Microbial degradation is a major determinant of the fate of pollutants in the environment. para-Nitrophenol (PNP) is an EPA listed priority pollutant with a wide environmental distribution, but little is known about the microorganisms that degrade it in the environment. We studied the diversity of active PNP-degrading bacterial populations in river water using a novel functional marker approach coupled with [13C6]PNP stable isotope probing (SIP). Culturing together with culture-independent terminal restriction fragment length polymorphism analysis of 16S rRNA gene amplicons identified Pseudomonas syringae to be the major driver of PNP degradation in river water microcosms. This was confirmed by SIP-pyrosequencing of amplified 16S rRNA. Similarly, functional gene analysis showed that degradation followed the Gram-negative bacterial pathway and involved pnpA from Pseudomonas spp. However, analysis of maleylacetate reductase (encoded by mar), an enzyme common to late stages of both Gram-negative and Gram-positive bacterial PNP degradation pathways, identified a diverse assemblage of bacteria associated with PNP degradation, suggesting that mar has limited use as a specific marker of PNP biodegradation. Both the pnpA and mar genes were detected in a PNP-degrading isolate, P. syringae AKHD2, which was isolated from river water. Our results suggest that PNP-degrading cultures of Pseudomonas spp. are representative of environmental PNP-degrading populations.

Becoming a region, becoming global, becoming imperceptable: territorialising salmon in Chilean Patagonia

Our article focuses on the region of Chilean Patagonia and considers how it has developed as a leading producer of salmon for global food markets. It addresses the problem of how to decentre conventional views of the forces driving regional development that give primacy to the role of capital and technology, instead giving due recognition to the knowledge and practices of situated actors and to the relationships that form between human and non-human entities in food producing regions. As an alternative, we ask whether an assemblage approach can improve our understanding of regional transformation. To explore this question, we present original ethnographic data on constitutive practices that have transformed the Patagonian region, from the territorialization of Salmonidae species to experimentation in ocean ranching and sea water fish farming, and finally the development of a global industry. The evidence leads us to argue that in a complex globalised world, assemblage theory offers a valuable approach for understanding how regional potential is realised. In the case of Chilean Patagonia, it is apparent that forms of bio-power generate new relations between life, agency and nature, stimulating contemporary regional transformations in ways overlooked by the lineal logic of capital objectification discourses. Applying an assemblage approach enables the significance of new contemporary human – non-human relationships and inter-subjectivities to come to the fore, keeping the social in view as potential for regional transformation and new power asymmetries continuously emerge.

From warfare to welfare: veterans, military charities and the blurred spatiality of post-service welfare in the United Kingdom

The military offers a form of welfare-for-work but when personnel leave they lose this safety net, a loss exacerbated by the rollback neoliberalism of the contemporary welfare state. Increasingly the third sector has stepped in to address veterans’ welfare needs through operating within and across military/civilian and state/market/community spaces and cultures. In this paper we use both veterans’ and military charities’ experiences to analyse the complex politics that govern the liminal boundary zone of post-military welfare. Through exploring ‘crossing’ and ‘bridging’ we conceptualise military charities as ‘boundary subjects’, active yet dependent on the continuation of the civilian-military binary, and argue that the latter is better understood as a multidirectional, multiscalar and contextual continuum. Post-military welfare emerges as a competitive, confused and confusing assemblage that needs to be made more navigable in order to better support the ‘heroic poor’.

The heterogeneity of wooded-agricultural landscape mosaics influences woodland bird community assemblages

Context Landscape heterogeneity (the composition and configuration of different landcover types) plays a key role in shaping woodland bird assemblages in wooded-agricultural mosaics. Understanding how species respond to landscape factors could contribute to preventing further decline of woodland bird populations. Objective To investigate how woodland birds with different species traits respond to landscape heterogeneity, and to identify whether specific landcover types are important for maintaining diverse populations in wooded-agricultural environments. Methods Birds were sampled from woodlands in 58 2 x 2 km tetrads across southern Britain. Landscape heterogeneity was quantified for each tetrad. Bird assemblage response was determined using redundancy analysis combined with variation partitioning and response trait analyses. Results For woodland bird assemblages, the independent explanatory importance of landscape composition and landscape configuration variables were closely interrelated. When considered simultaneously during variation partitioning, the community response was better represented by compositional variables. Different species responded to different landscape features and this could be explained by traits relating to woodland association, foraging strata and nest location. Ubiquitous, generalist species, many of which were hole-nesters or ground foragers, correlated positively with urban landcover while specialists of broadleaved woodland avoided landscapes containing urban areas. Species typical of coniferous woodland correlated with large conifer plantations. Conclusions At the 2 x 2 km scale, there was evidence that the availability of resources provided by proximate landcover types was highly important for shaping woodland bird assemblages. Further research to disentangle the effects of composition and configuration at different spatial scales is advocated.

Moving on in Neolithic studies: understanding mobile lives

Mobility is a fundamental facet of being human and should be central to archaeology. Yet mobility itself and the role it plays in the production of social life, is rarely considered as a subject in its own right. This is particularly so with discussions of the Neolithic people where mobility is often framed as being somewhere between a sedentary existence and nomadic movements. This volume examines the importance and complexities of movement and mobility, whether on land or water, in the Neolithic period. It uses movement in its widest sense, ranging from everyday mobilities – the routines and rhythms of daily life – to proscribed mobility, such as movement in and around monuments, and occasional and large-scale movements and migrations around the continent and across seas. Papers are roughly grouped and focus on ‘mobility and the landscape’, ‘monuments and mobility’, ‘travelling by water’, and ‘materials and mobility’. Through these themes the volume considers the movement of people, ideas, animals, objects, and information, and uses a wide range of archaeological evidence from isotope analysis; artefact studies; lithic scatters and assemblage diversity.

Culex pipiens development is greatly influenced by native bacteria and exogenous yeast

Culex pipiens is the most cosmopolitan mosquito of the Pipiens Assemblage. By studying the nature of interactions between this species and microorganisms common to its breeding environment we can unravel important pitfalls encountered during development. We tested the survival rate of larval stages, pupae and adults of a Cx. pipiens colony exposed to a variety of microorganisms in laboratory conditions and assessed the transmission to offspring (F1) by those organisms that secured development up to adulthood. Three complementary experiments were designed to: 1) explore the nutritional value of yeasts and other microorganisms during Cx. pipiens development; 2) elucidate the transstadial transmission of yeast to the host offspring; and 3) to examine the relevance of all these microorganisms in female choice for oviposition-substratum. The yeast Saccharomyces cerevisiae proved to be the most nutritional diet, but despite showing the highest survival rates, vertical transmission to F1 was never confirmed. In addition, during the oviposition trials, none of the gravid females was attracted to the yeast substratum. Notably, the two native bacterial strains, Klebsiella sp. and Aeromonas sp., were the preferred oviposition media, the same two bacteria that managed to feed neonates until molting into 2nd instar larvae. Our results not only suggest that Klebsiella sp. or Aeromonas sp. serve as attractants for oviposition habitat selection, but also nurture the most fragile instar, L1, to assure molting into a more resilient stage, L2, while yeast proves to be the most supportive diet for completing development. These experiments unearthed survival traits that might be considered in the future development of strategies of Cx. pipiens control. These studies can be extended to other members of the Pipiens Assemblage

Detection of assemblages A and B of Giardia duodenalis in water and sewage from Sao Paulo state, Brazil

Giardia duodenalis is a protozoan that parasitizes humans and other mammals and causes giardiasis. Although its isolates have been divided into seven assemblages, named A to G, only A and B have been detected in human faeces. Assemblage A isolates are commonly divided into two genotypes, AI and AII. Even though information about the presence of this protozoan in water and sewage is available in Brazil, it is important to verify the distribution of different assemblages that might be present, which can only be done by genotyping techniques. A total of 24 raw and treated sewage, surface and spring water samples were collected, concentrated and purified. DNA was extracted, and a nested PCR was used to amplify an 890 bp fragment of the gdh gene of G. duodenalis, which codes for glutamate dehydrogenase. Positive samples were cloned and sequenced. Ten out of 24 (41.6%) samples were confirmed to be positive for G. duodenalis by sequencing. Phylogenetic analysis grouped most sequences with G. duodenalis genotype AII from GenBank. Only two raw sewage samples presented sequences assigned to assemblage B. In one of these samples genotype AII was also detected. As these assemblages/genotypes are commonly associated to human giardiasis, the contact with these matrices represents risk for public health.

The occurrence of Laurencia marilzae (Ceramiales, Rhodophyta) in Brazil based on morphological and molecular data

Laurencia marilzae is recorded for the first time from the western Atlantic Ocean; it was found in Laje de Santos Marine State Park, Sao Paulo, southeastern Brazil. The specimens were collected in the rocky subtidal zone from 7 to 15 m depth. The most distinctive characteristic of this species is the presence of corps en cerise in all cells of the thallus, including cortex, medulla, and trichoblasts. The phylogenetic position of the species was inferred by analysis of the chloroplast-encoded rbcL gene sequences from 43 taxa, using two other rhodomelacean taxa and two members of the Ceramiaceae as outgroups. Within the Laurencia assemblage, L. marilzae from Brazil and from the Canary Islands ( type locality) formed a distinctive lineage sister to all other Laurencia species analyzed. Male plants are described for the first time. This study expands the geographical distribution of L. marilzae to the western Atlantic Ocean.

Temporal Diversity Patterns and Phenology in Fruit-feeding Butterflies in the Atlantic Forest

The Atlantic Forest deserves special attention due to its high level of species endemism and degree of threat. As in other tropical biomes, there is little information about the ecology of the organisms that occur there. The objectives of this study were to verify how fruit-feeding butterflies are distributed through time, and the relation with meteorological conditions. Species richness and Shannon index were partitioned additively at the monthly level, and beta diversity, used as a hierarchical measure of temporal species turnover, was calculated among months, trimesters, and semesters. Circular analysis was used to verify how butterflies are distributed along seasons and its relation with meteorological conditions. We sampled 6488 individuals of 73 species. Temporal diversity of butterflies was more grouped than expected by chance among the months of each trimester. Circular analyses revealed that diversity is concentrated in hot months (September-March), with the subfamily Brassolinae strongly concentrated in February-March. Average temperature was correlated with total abundance of butterflies, abundance of Biblidinae, Brassolinae and Morphinae, and richness of Satyrinae. The present results show that 3mo of sampling between September and March is enough to produce a nonbiased sample of the local assemblage of butterflies, containing at least 70 percent of the richness and 25 percent of abundance. The influence of temperature on sampling is probably related to butterfly physiology. Moreover, temperature affects resource availability for larvae and adults, which is higher in hot months. The difference in seasonality patterns among subfamilies is probably a consequence of different evolutionary pressures through time.

Behavioral suites mediate group-level foraging dynamics in communities of tropical stingless bees

Competition for floral resources is a key force shaping pollinator communities, particularly among social bees. The ability of social bees to recruit nestmates for group foraging is hypothesized to be a major factor in their ability to dominate rich resources such as mass-flowering trees. We tested the role of group foraging in attaining dominance by stingless bees, eusocial tropical pollinators that exhibit high diversity in foraging strategies. We provide the first experimental evidence that meliponine group foraging strategies, large colony sizes and aggressive behavior form a suite of traits that enable colonies to improve dominance of rich resources. Using a diverse assemblage of Brazilian stingless bee species and an array of artificial ""flowers"" that provided a sucrose reward, we compared species` dominance and visitation under unrestricted foraging conditions and with experimental removal of group-foraging species. Dominance does not vary with individual body size, but rather with foraging group size. Species that recruit larger numbers of nestmates (Scaptotrigona aff. depilis, Trigona hyalinata, Trigona spinipes) dominated both numerically (high local abundance) and behaviorally (controlling feeders). Removal of group-foraging species increased feeding opportunities for solitary foragers (Frieseomelitta varia, Melipona quadrifasciata and Nannotrigona testaceicornis). Trigona hyalinata always dominated under unrestricted conditions. When this species was removed, T. spinipes or S. aff. depilis controlled feeders and limited visitation by solitary-foraging species. Because bee foraging patterns determine plant pollination success, understanding the forces that shape these patterns is crucial to ensuring pollination of both crops and natural areas in the face of current pollinator declines.

Non-homologous sex chromosomes in two species of the genus Eigenmannia (Teleostei : Gymnotiformes)

The Neotropical genus Eigenmannia is a fish group with unknown species diversity where representatives possess a broad range of chromosomal sex determining systems namely XY/XX, X1X2Y/X1X1X2X2, ZZ/ZW as well as homomorphic sex chromosomes. To test the homology of two heteromorphic XY sex chromosome systems present in two sympatric populations, reciprocal cross-species FISH experiments were performed using probes derived by microdissection of X and Y chromosomes present in analyzed specimens of Eigenmannia virescens and Eigenmannia sp.2, respectively. While X and Y paint probes hybridized to species-specific sex chromosomes, in reciprocal cross-FISH both probes hybridized exclusively to autosomes. The result suggests multiple independent origins of the XY systems in the analyzed populations. Copyright (C) 2008 S. Karger AG, Basel.

A comparative study of cleaning activity of two reef fishes at Fernando de Noronha Archipelago, tropical West Atlantic

Cleaner fishes are usually classified as obligate or facultative cleaners according to their diet and the extent to which their nutritional requirements in the different ontogenetic stages are gained from cleaning. While obligate cleaners clean throughout their lives and ingest mainly food taken from the clients` body surface, facultative cleaners clean only as juveniles and have a broader diet. In addition, some facultative cleaners may experience a relatively higher predation risk, and thus rarely interact with piscivorous fishes. Despite these acknowledged differences, there are very few studies that compare cleaning activity of obligate and facultative cleaners within the same area. Cleaning activity of the obligate cleaner goby Elacatinus cf. randalli and the facultative cleaner wrasse Thalassoma noronhanum were comparatively examined at Fernando de Noronha Archipelago, tropical West Atlantic. The client assemblage attended by the two cleaners differed, as the goby attended a slightly greater diversity of species (22), mostly piscivores and zoobenthivores, and the wrasse attended fewer species (19), mostly planktivores. Chromis multilineata was the most common client species of both cleaners, although body size (which is expected to be positively correlated to clients` ectoparasite load) of C. multilineata individuals attended by the goby was larger than that of the individuals attended by the wrasse. Despite such differences, T. noronhanum showed a surprisingly species-rich client assemblage when compared with other cleaners of the genus Thalassoma. In addition, the frequency and time spent on cleaning interactions, as well as the number of client species attended per 10-min period, was similar for both cleaner species, which indicate that they have important yet complimentary ecological roles in the reef community at Fernando de Noronha Archipelago.

Non-random reef use by fishes at two dominant zones in a tropical, algal-dominated coastal reef

Habitat use and the processes which determine fish distribution were evaluated at the reef flat and reef crest zones of a tropical, algal-dominated reef. Our comparisons indicated significant differences in the majority of the evaluated environmental characteristics between zones. Also, significant differences in the abundances of twelve, from thirteen analyzed species, were observed within and between-sites. According to null models, non-random patterns of species co-occurrences were significant, suggesting that fish guilds in both zones were non-randomly structured. Unexpectedly, structural complexity negatively affected overall species richness, but had a major positive influence on highly site-attached species such as a damselfish. Depth and substrate composition, particularly macroalgae cover, were positive determinants for the fish assemblage structure in the studied reef, prevailing over factors such as structural complexity and live coral cover. Our results are conflicting with other studies carried out in coral-dominated reefs of the Caribbean and Pacific, therefore supporting the idea that the factors which may potentially influence reef fish composition are highly site-dependent and variable.